José Angel Hernández-Rivas

Successful discontinuation of eltrombopag after complete remission in patients with primary immune thrombocytopenia

Eltrombopag is effective and safe in immune thrombocytopenia (ITP). Some patients may sustain their platelet response when treatment is withdrawn but the frequency of this phenomenon is unknown. We retrospectively evaluated 260 adult primary ITP patients (165 women and 95 men; median age, 62 years) treated with eltrombopag after a median time from diagnosis of 24 months. Among the 201 patients who achieved a complete remission (platelet count >100 × 109/l), eltrombopag was discontinued in 80 patients. Reasons for eltrombopag discontinuation were: persistent response despite a reduction in dose over time (n = 33), platelet count >400 × 109/l (n = 29), patients request (n = 5), elevated aspartate aminotransferase (n = 3), diarrhea (n = 3), thrombosis (n = 3), and other reasons (n = 4). Of the 49 evaluable patients, 26 patients showed sustained response after discontinuing eltrombopag without additional ITP therapy, with a median follow‐up of 9 (range, 6–25) months. These patients were characterized by a median time since ITP diagnosis of 46.5 months, with 4/26 having ITP < 1 year. Eleven patients were male and their median age was 59 years. They received a median of 4 previous treatment lines and 42% were splenectomized. No predictive factors of sustained response after eltrombopag withdrawal were identified. Platelet response following eltrombopag cessation may be sustained in an important percentage of adult primary ITP patients who achieved CR with eltrombopag. However, reliable markers for predicting which patients will have this response are needed. Am. J. Hematol. 90:E40–E43, 2015.

Efficacy, pharmacokinetics, and safety of the biosimilar CT-P10 compared with rituximab in patients with previously untreated advanced-stage follicular lymphoma: a randomised, double-blind, parallel-group, non-inferiority phase 3 trial

BACKGROUND Studies in patients with rheumatoid arthritis have shown that the rituximab biosimilar CT-P10 (Celltrion, Incheon, South Korea) has equivalent efficacy and pharmacokinetics to rituximab. In this phase 3 study, we aimed to assess the non-inferior efficacy and pharmacokinetic equivalence of CT-P10 compared with rituximab, when used in combination with cyclophosphamide, vincristine, and prednisone (CVP) in patients with newly diagnosed advanced-stage follicular lymphoma. METHODS In this ongoing, randomised, double-blind, parallel-group, active-controlled study, patients aged 18 years or older with Ann Arbor stage III-IV follicular lymphoma were assigned 1:1 to CVP plus intravenous infusions of 375 mg/m2 CT-P10 or rituximab on day 1 of eight 21-day cycles. Randomisation was done by the investigators using an interactive web or voice response system and a computer-generated randomisation schedule, prepared by a clinical research organisation. Randomisation was balanced using permuted blocks and was stratified by country, gender, and Follicular Lymphoma International Prognostic Index score (0-2 vs 3-5). Study teams from the sponsor and clinical research organisation, investigators, and patients were masked to treatment assignment. The study was divided into two parts: part 1 assessing equivalence of pharmacokinetics (in the pharmacokinetics subset), and part 2 assessing efficacy in all randomised patients (patients from the pharmacokinetics subset plus additional patients enrolled in part 2). Equivalence of pharmacokinetics was shown if the 90% CIs for the geometric mean ratio of CT-P10 to rituximab in AUCτ and CmaxSS were within the bounds of the equivalence margin of 80% and 125%. Non-inferiority of response was shown if the one-sided 97·5% CI lay on the positive side of the -7% margin, using a one-sided test done at the 2·5% significance level. The primary efficacy endpoint was the proportion of patients who had an overall response over eight cycles and was assessed in the efficacy population (all randomised patients). The primary pharmacokinetic endpoints were area under the serum concentration-time curve at steady state (AUCτ) and maximum serum concentration at steady state (CmaxSS) at cycle 4, assessed in the pharmokinetic population. This trial is registered with ClinicalTrials.gov, number NCT02162771. FINDINGS Between July 28, 2014, and Dec 29, 2015, 140 patients were enrolled. Here we report data for the eight-cycle induction period, up to week 24. The proportion of patients with an overall response in the efficacy population was 64 (97·0%) of 66 patients in the CT-P10 treatment group and 63 (92·6%) of 68 patients in the rituximab treatment group (4·3%; one-sided 97·5% CI -4·25), which lay on the positive side of the predefined non-inferiority margin. The ratio of geometric least squares means (CT-P10/rituximab) was 102·25% (90% CI 94·05-111·17) for AUCτ and 100·67% (93·84-108·00) for CmaxSS, with all CIs within the bioequivalence margin of 80-125%. Treatment-emergent adverse events were reported for 58 (83%) of 70 patients in the CT-P10 treatment group and 56 (80%) of 70 in the rituximab treatment group. The most common grade 3 or 4 treatment-emergent adverse event in each treatment group was neutropenia (grade 3, 15 [21%] of 70 patients in the CT-P10 group and seven [10%] of 70 patients in the rituximab group). The proportion of patients who experienced at least one treatment-emergent serious adverse event was 16 (23%) of 70 patients in the CT-P10 group and nine (13%) of 70 patients in the rituximab group. INTERPRETATION In this study, we show that CT-P10 exhibits non-inferior efficacy and pharmacokinetic equivalence to rituximab. The safety profile of CT-P10 was comparable to that of rituximab. CT-P10 might represent a new therapeutic option for advanced-stage follicular lymphoma. FUNDING Celltrion, Inc.

Risk of thrombosis according to need of phlebotomies in patients with polycythemia vera treated with hydroxyurea.

Hematocrit control below 45% is associated with a lower rate of thrombosis in polycythemia vera. In patients receiving hydroxyurea, this target can be achieved with hydroxyurea alone or with the combination of hydroxyurea plus phlebotomies. However, the clinical implications of phlebotomy requirement under hydroxyurea therapy are unknown. The aim of this study was to evaluate the need for additional phlebotomies during the first five years of hydroxyurea therapy in 533 patients with polycythemia vera. Patients requiring 3 or more phlebotomies per year (n=85, 16%) showed a worse hematocrit control than those requiring 2 or less phlebotomies per year (n=448, 84%). There were no significant differences between the two study groups regarding leukocyte and platelet counts. Patients requiring 3 or more phlebotomies per year received significantly higher doses of hydroxyurea than the remaining patients. A significant higher rate of thrombosis was found in patients treated with hydroxyurea plus 3 or more phlebotomies per year compared to hydroxyurea with 0–2 phlebotomies per year (20.5% vs. 5.3% at 3 years; P<0.0001). In multivariate analysis, independent risk factors for thrombosis were phlebotomy dependency (HR: 3.3, 95%CI: 1.5–6.9; P=0.002) and thrombosis at diagnosis (HR: 4.7, 95%CI: 2.3–9.8; P<0.0001). The proportion of patients fulfilling the European LeukemiaNet criteria of resistance/intolerance to hydroxyurea was significantly higher in the group requiring 3 or more phlebotomies per year (18.7% vs. 7.1%; P=0.001) mainly due to extrahematologic toxicity. In conclusion, phlebotomy requirement under hydroxyurea therapy identifies a subset of patients with increased proliferation of polycythemia vera and higher risk of thrombosis.

Eltrombopag safety and efficacy for primary chronic immune thrombocytopenia in clinical practice

Eltrombopag is effective and safe in chronic immune thrombocytopenia (ITP). However, clinical trials may not accurately reflect what happens in clinical practice. We evaluated the efficacy and safety of eltrombopag in primary chronic ITP in a real‐world setting.

Do chronic myeloid leukemia patients with late “warning” responses benefit from “watch and wait” or switching therapy to a second generation tyrosine kinase inhibitor?

In the latest recommendations for the management of chronic‐phase chronic myeloid leukemia suboptimal responses have been reclassified as “warning responses.” In contrast to previous recommendations current guidance advises close monitoring without changing therapy. We have identified 198 patients treated with first‐line imatinib, with a warning response after 12 months of treatment (patients with a complete cytogenetic response but no major molecular response [MMR]). One hundred and forty‐six patients remained on imatinib, while 52 patients changed treatment to a second generation tyrosine kinase inhibitor (2GTKI). Changing therapy did not correlate with an increase in overall survival or progression‐free survival. Nevertheless, a significant improvement was observed in the probability of a MMR: 24% vs. 42% by 12 months and 43% vs. 64% by 24 months (P = 0.002); as well as the probability of achieving a deep molecular responses (MR4.5): 1% vs. 17% and 7% vs. 23% by 12 and 24 months, respectively (P = <0.001) .The treatment change to 2GTKI remained safe; however, we have observed a 19% of treatment discontinuation due to side effects. We have observed an improvement of molecular responses after changing treatment to 2GTKI in patients with late suboptimal response treated with imatinib first line. However, these benefits were not correlated with an improvement of progression free survival or overall survival. Am. J. Hematol. 89:E206–E211, 2014.